Photographic paper exposing method and an optical digital printer employing this method

Abstract

An optical digital printer comprising a paper storage (PM 1 ) for storing photographic paper in roll form, a digital printing unit ( 2 ) having an irradiating surface ( 42 ) for line-exposing the photographic paper based on image data, a developing unit ( 300 ) for developing the photographic paper exposed by the digital printing unit, a transport mechanism for transporting the photographic paper along a paper transport line extending from the paper storage to the developing unit, a first paper accommodating box (RB 1 ) disposed between the paper storage (PM 1 ) and the digital printing unit ( 2 ), and a second paper accommodating box (RB 2 ) disposed between the digital printing unit and the developing unit ( 300 ). The transport mechanism includes a paper loader ( 20 ) for feeding the photographic paper transported from the paper storage into the first paper accommodating box, an exposure control roller ( 44 ) for drawing the photographic paper from the first paper accommodating box and causing the photographic paper to move past the irradiating surface ( 42 ), and, in time of exposure, for causing the photographic paper to move past the irradiating surface while feeding the photographic paper back into the first paper accommodating box, and a paper transport direction switcher ( 70 ) for selectively feeding the photographic paper having moved past the irradiating surface, without being exposed, toward the second paper accommodating box, and feeding the photographic paper having moved past and exposed by the irradiating surface toward the developing unit.

What is claimed is:  
     
       1. An optical digital printer comprising: 
       a transporting mechanism for transporting photographic paper along a paper transport line extending from a paper storage to a developing unit;  
       an exposure unit for printing a plurality of images on said photographic paper transported backward toward said paper storage by said transport mechanism, by irradiating said photographic paper with light based on image data;  
       a cutter for cutting a part of the photographic paper exposed with said plurality of images; and  
       a siding line for shunting part of said photographic paper fed by a length sufficient to print said plurality of images in said exposure unit, said siding line being blanched from said paper transport line downnstream of said exposure unit and upstream of said cutter, wherein a paper transport direction switcher for switching over feeding direction of the photographic paper between said transport line extending to said cutter and said siding line is provided between said exposure unit and said cutter.  
     
     
       2. An optical digital printer comprising: 
       a transporting mechanism for transporting photographic paper along a paper transport line extending from a paper storage to a developing unit;  
       an exposure unit for printing an image on said photographic paper transported backward toward said paper storage by said transport mechanism, by irradiating said photographic paper with light based on image data;  
       a cutter for cutting a part of the photographic paper exposed with said image; and  
       a siding line for shunting part of said photographic paper fed by a length sufficient to print said image in said exposure unit, said siding line being branched from said paper transport line downstream of said exposure unit and upstream of said cutter, wherein a paper transport direction switcher for switching over feeding direction of the photographic paper between said transport line extending to said cutter and said siding line is provided between said exposure unit and said cutter.  
     
     
       3. A photographic paper exposing method for printing images on photographic paper drawn out of a paper storage by irradiating the photographic paper with light based on image data, said method comprising: 
       a first step, executed for printing a plurality of images on said photographic paper, of feeding said photographic paper by a length sufficient to print said plurality of images, past an irradiating point to a position downstream thereof;  
       a second step of successively printing said plurality of images on said photographic paper at said irradiating point while drawing said photographic paper set at said downstream position at said first step backward to an upstream side; and  
       a third step of feeding said photographic paper to a paper transport line extending to a developing unit, wherein the method is conducted with the optical digital printer of  claim 2 .  
     
     
       4. A photographic paper exposing method for printing images on photographic paper drawn out of a paper storage by irradiating the photographic paper with light based on image data, said method comprising: 
       a first step, executed for printing a plurality of images on said photographic paper, of feeding, along a paper transport line, said photographic paper by a length sufficient to print said plurality of images, past an irradiating point to a position dowistream thereof;  
       a second step of successively printing said plurality of images on said photographic paper at said irradiating point while drawing said photographic paper set at said downstream position at said first step backward to an upstream side; and  
       a third step of cutting apart of the photographic paper exposed with said plurality of images by a cutter disposed downstream of said irradiating point and feeding said part to said paper transport line extending to a developing unit;  
       wherein at said first step, part of said photographic paper is shunted to a siding line branched from said paper transport line at a position upstream of said cutter, wherein the method is conducted with the optical digital printer of  claim 2 .  
     
     
       5. A photographic paper exposing method for printing images on photographic paper drawn out of a paper storage by irradiating the photographic paper with light based on image data, said method comprising: 
       a first step, executed for printing an image on said photographic paper, of feeding, along a paper transport line, said photographic paper by a length sufficient to print said image, past an irradiating point to a position downstream thereof;  
       second step of successively printing said image on said photographic paper at said irradiating point while drawing said photographic paper set at said downstream position at said first step backward to an upstream side; and  
       a third step of cutting a part of the photographic paper exposed with said image by a cutter disposed downstream of said irradiating point and feeding said pail to said paper transport line extending to a developing unit;  
       wherein at said first step, part of said photographic paper is shunted to a siding line branched from said paper transport line at a position upstream of said cutter, wherein the method is conducted with the optical digital printer of  claim 2 .